The isolation and structure determination of cyclic peptide alkaloids, discarine-M and discarine-N, along with seven known cyclic peptide alkaloids, adouetine-Y', franganine, frangulanine, discarines-A, -B, -C, and -D from the root bark of Discaria americana are described. Structures were determined spectroscopically, especially using 2D NMR spectroscopic analysis. The crude methanol extract, the basic ether extract, and the alkaloids 6 and 7 also weakly inhibited growth of gram-negative and gram-positive bacteria.
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http://dx.doi.org/10.1016/j.phytochem.2004.02.006 | DOI Listing |
J Nat Prod
January 2025
Department of Chemistry and Biological Engineering, Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata 992-8510, Japan.
We investigated the chemical structures and conformational isomers of the cyclic heptapeptides stylissamide H and euryjanicin A isolated from marine sources. Despite sharing the same molecular structure, stylissamide H and euryjanicin A exhibit different conformational isomers in solution and solid states. The main difference arises from the configurations of the two Pro residues.
View Article and Find Full Text PDFCommun Chem
January 2025
Agri-Bio Research Center, Kaneka Corporation, Takasago, Hyogo, Japan.
Cyclic lipopeptides (CLPs) produced by the genus Bacillus are amphiphiles composed of hydrophilic amino acid and hydrophobic fatty acid moieties and are biosynthesised by non-ribosomal peptide synthetases (NRPSs). CLPs are produced as a mixture of homologues with different fatty acid moieties, whose length affects CLP activity. Iturin family lipopeptides are a family of CLPs comprising cyclic heptapeptides and β-amino fatty acids and have antimicrobial activity.
View Article and Find Full Text PDFArch Dermatol Res
January 2025
Lűbeck Institute of Experimental Dermatology, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany.
Background: A low risk of cardiovascular and metabolic outcomes was found in the randomized clinical trials of dupilumab in atopic dermatitis (AD). Dupilumab-associated real-life long-term cardiometabolic risk relative to other systemic agents is yet to be precisely investigated.
Objective: To assess the risk of cardiometabolic outcomes in patients with AD treated with dupilumab relative to those treated with methotrexate and cyclosporine.
Exp Neurol
January 2025
Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA. Electronic address:
Hypoxic-ischemic (HI) brain injury is a common neurological problem in neonates. The postsynaptic density protein-95 (PSD-95) is an excitatory synaptic scaffolding protein that regulates synaptic function, and represents a potential therapeutic target to attenuate HI brain injury. Syn3 and d-Syn3 are novel high affinity cyclic peptides that bind the PDZ3 domain of PSD-95.
View Article and Find Full Text PDFToxicol Appl Pharmacol
January 2025
Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao 266000, China. Electronic address:
The incidence rate and mortality rate of breast cancer remain high, and there is an urgent need for safe and effective drugs. The excellent biological activity of hesperidin (HE) is a potential drug for the treatment of breast cancer. In this study, silk fibroin peptides (SFP) were used as delivery carriers and HE loaded SFP nanofibers (SFP/HE NFs) was prepared.
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